An engine of a vehicle may be automatically stopped when if there is no immediate need for the engine's torque output. The engine may be restarted if a greater amount of torque is requested to propel the vehicle. Further, if the vehicle is a hybrid vehicle, it may be desirable to open a driveline disconnect clutch when engine rotation is being stopped so that a driveline integrated starter/generator may efficiently provide torque to propel the vehicle. The driveline disconnect clutch may be closed and the engine may be restarted when a driver demand torque increases. However, frequently starting and stopping the vehicle may increase electrical energy consumption of the vehicle. Further, if the engine has to restart to provide low levels of vehicle acceleration, stopping the engine may not conserve as much fuel as is desired and vehicle driveline degradation may increase.
The inventors herein have recognized the above-mentioned disadvantages and have developed a method for operating an engine of a vehicle, comprising: in an engine start/stop mode, selectively automatically stopping and starting the engine in response to vehicle operating conditions while a transmission of the vehicle is in a forward gear; and deactivating the engine start/stop mode in response to an electrical load of a trailer coupled to the vehicle.
By deactivating an engine start/stop mode in response to an electrical load of a trailer coupled to a vehicle, it may be possible to provide the technical result of reducing electrical consumption and maintaining battery state of charge so that the vehicle may be reliably restarted. Additionally, the engine start/stop mode may be deactivated in response to vehicle mass and/or the combined mass of the vehicle and a trailer. Consequently, the vehicle may respond more rapidly and with more torque than compared to if the vehicle were operated in an engine start/stop mode. Thus, vehicle launch may be improved by deactivating the engine start/stop mode.
The present description may provide several advantages. In particular, the approach may reduce electrical energy consumption by a vehicle so that there may be sufficient electrical energy to restart an engine of the vehicle. Further, the approach may improve launch of a vehicle from stop when a trailer is coupled to the vehicle. Further still, the approach may reduce driveline wear, thereby increasing the operating life of the driveline.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.